Underwater Noise

Monitoring of noise input into the sea

Due to the intended energy revolution Germany seeks to realize, the expansion of renewable energy sources is both, politically and economically, heavily being pushed in Germany. In order to meet the aims of the energy revolution, a significant share of the future electricity demand shall be covered by the expansion of offshore wind farms.

The construction and the operation of offshore wind farms cause considerable noise inputs into the surrounding waters, in addition to the already existent shipping noise. This results in a continuously increasing noise exposure of the seas, which can have negative impacts on the marine animals.

Germany is the first country worldwide, which has defined a limit value for impulsive noise inputs into the water in 2011. Therefore, a biological monitoring is usually required. The metrological record of underwater noise becomes more and more a main descriptor, which increasingly takes on significance.

The itap GmbH, as a DAkkS-accredited test laboratory according to DIN EN ISO/IEC 17025, is entitled to perform immission and emission measurements for continuous noise and impulsive noise entries into the water, as well as forecasts for underwater noise recordings. Overall, the itap GmbH offers the following services in the field of underwater noise:

forecast of the underwater noise (continuous and impulsive noise)
continuous noise and impulsive underwater noise measurements e. g. according to ISO 18406 or the BSH measuring specification
consultation on acoustic questions about noise entries into the water and reduction of underwater noise
evaluation of noise reduction measures according to DIN SPEC 45653
measurements of structural vibrations

Hydro-acoustic online monitoring with radio transmission

Within this field, we offer the following services

Prognosis of underwater noise immissions

for impulsive sound (e. g. piling noise) and continuous sound of e. g. Offshore Windfarms (e. g. operational sound) according to national guidelines and project-specific requirements of the approval authorities (e. g. in Germany according to StUK and the BSH guideline; Denmark according to the directive of the Energy Ministry)

Underwater noise measurements (Hydroacoustics)

for impulsive sound and continuous sound according to national guidelines and project-specific requirements
experiences with underwater noise measurements are available in Germany, the Netherlands, Denmark, UK and Sweden
environmental sounds/background noises
impulse noise at construction sites (e. g. pile driving, detonations)
operating noises of offshore wind turbines
at port facilities, in coastal waters and at sea (offshore)
for environmental compatibility studies

Consulting services

preparation of noise protection concepts
selection of noise mitigation measures for construction site activities
support in the plan approval procedure and approval procedure

Research

in the field of underwater sound propagation and further development of noise mitigation measures and the evaluation of hydro sound immissions on the marine environment

Underwater Piling Noise Demo

The following audio examples are sorted by the distance to the driven pile and divided into piling noise with and without applied noise mitigation system.
The differences of “volume” of the audio examples correspond to the real level differences.

Without noise protection